Thanks toaster. I actually have that stored in my files also. I guess if you're around long enough it's a "must have" part of the knowledge-base. Lol!

In closed loop, the ecu and O2 sensors will target AFR of 14.7. Old injectors or new injectors it will still target 14.7.

70-75mph and A/C on in a cherokee, you can only expect poor mileage at best.

Lol! I hear you Marty. It's a good thing I'm not concerned about the price of fuel, it's not a DD and we were only doing 70-75 mph. Maybe it's just my perception, but, it did seem to consume more than it did prior to swap.

As I said, I'm very happy with the running of it. It's running better than it ever has. Just didn't know if there may be something else I need to be aware of.

Thanks. :thumbup1:

Are you guys sure we don't have to tune for the new flow rates? I've been hesitant to do this swap. In the Vette when I went from 28# to 36# I had to have the car tuned. I'm no pro on the 4.0 though as I'm fairly new to it.

It's such a small difference in flow rates that the computer can self adjust for the injectors.

Don't let this thread turn you away from considering the swap. The benefits outweigh the negative aspects of the single-hole design of the OEM injectors.

As I've stated, I'm very happy with the results and they are noticeable.

I just upgraded my 2001 to the 784's. I haven't driven it too much since so I can't say anything about mileage, but I've been very happy in the hour or so that I've been in it since. The 4.0 wasn't running rough before, but it turns over immediately now, idles much much smoother and actually at a noticeably lower RPM, and does seem to have a little quicker throttle response. The butt-o-meter tells me nothing since I've been driving my 1995 Z28 a lot lately and the XJ will feel like a slug after that no matter what I do to it.

Keep in mind that all of these things may also just be due to the fact that I replaced old fuel injectors, but $50 for a set with new o-rings/pintles/cleaned/etc. is good even for a stock replacement.

XJwonders is correct I run the 784 on my 99 and the 703 is the correct injector for a 98 but some use others I know. I bet with a reset you will do a lot better is that all you changed?

Do you notice any rich conditions? I was looking at using the Ford xf2e-c4b as it is closer to the factory flow but still has the 4 hole pintle.

Yeah Fred, that's all I changed. I may do the reset when I have time like toaster suggested.

Thanks! Saved this to my files. New to having a 98 XJ

Improved fuel economy
 

Have you tried a lighter wife?

Adjust your sails, sailor. There's rough seas ahead.